1G8P

CRYSTAL STRUCTURE OF BCHI SUBUNIT OF MAGNESIUM CHELATASE

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Structure Motif: Primary M-CSA Annotation

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1g8pa_	Alpha and beta proteins (a/b)	P-loop containing nucleoside triphosphate hydrolases	P-loop containing nucleoside triphosphate hydrolases	Extended AAA-ATPase domain	ATPase subunit of magnesium chelatase, BchI	(Rhodobacter capsulatus ) [TaxId: 1061 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	Extended AAA-ATPase domain	8020312	4000283	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	RecA-like P-loop NTPases	8032692	3002019	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	MoxR	e1g8pA1	A: alpha arrays	X: Histone-like	H: Histone-related	T: AAA+ ATPase lid domain	F: MoxR	ECOD (1.6)
A	Sigma54_activat	e1g8pA2	A: a/b three-layered sandwiches	X: P-loop domains-like	H: P-loop domains-related	T: P-loop containing nucleoside triphosphate hydrolases	F: Sigma54_activat	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.40.50.300	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	P-loop containing nucleotide triphosphate hydrolases	CATH (4.3.0)
A	1.10.8.80	Mainly Alpha	Orthogonal Bundle	Helicase, Ruva Protein	domain 3	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF17863	AAA lid domain (AAA_lid_2)	AAA lid domain	This entry represents the alpha helical AAA+ lid domain that is found to the C-terminus of AAA domains.	Domain
A	PF01078	Magnesium chelatase, subunit ChlI (Mg_chelatase)	Magnesium chelatase, subunit ChlI	Magnesium-chelatase is a three-component enzyme that catalyses the insertion of Mg2+ into protoporphyrin IX. This is the first unique step in the synthesis of (bacterio)chlorophyll. Due to this, it is thought that Mg-chelatase has an important ro ...	Magnesium-chelatase is a three-component enzyme that catalyses the insertion of Mg2+ into protoporphyrin IX. This is the first unique step in the synthesis of (bacterio)chlorophyll. Due to this, it is thought that Mg-chelatase has an important role in channelling inter- mediates into the (bacterio)chlorophyll branch in response to conditions suitable for photosynthetic growth. ChlI and BchD have molecular weight between 38-42 kDa.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	MAGNESIUM-CHELATASE 38 KDA SUBUNIT	binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding organic cyclic compound binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding organic cyclic compound binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding pyrophosphatase activity ATP hydrolysis activity ribonucleoside triphosphate phosphatase activity hydrolase activity, acting on acid anhydrides, in phosphorus-containing anhydrides hydrolase activity hydrolase activity, acting on acid anhydrides catalytic activity ATP-dependent activity ligase activity, forming nitrogen-metal bonds ligase activity, forming nitrogen-metal bonds, forming coordination complexes magnesium chelatase activity ligase activity	photosynthesis cellular metabolic process metabolic process cellular process pigment metabolic process organonitrogen compound metabolic process porphyrin-containing compound biosynthetic process tetrapyrrole metabolic process chlorophyll metabolic process organonitrogen compound biosynthetic process bacteriochlorophyll metabolic process pigment biosynthetic process bacteriochlorophyll biosynthetic process organic cyclic compound metabolic process photosynthesis cellular metabolic process metabolic process cellular process pigment metabolic process organonitrogen compound metabolic process porphyrin-containing compound biosynthetic process tetrapyrrole metabolic process chlorophyll metabolic process organonitrogen compound biosynthetic process bacteriochlorophyll metabolic process pigment biosynthetic process bacteriochlorophyll biosynthetic process organic cyclic compound metabolic process organic substance metabolic process tetrapyrrole biosynthetic process biosynthetic process organic cyclic compound biosynthetic process organic substance biosynthetic process porphyrin-containing compound metabolic process chlorophyll biosynthetic process	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR011775	Magnesium chelatase, ATPase subunit I	Family
A	IPR045006	Magnesium-chelatase subunit ChlI-like	Family
A	IPR041628	ChlI/MoxR, AAA lid domain	Domain
A	IPR003593	AAA+ ATPase domain	Domain
A	IPR000523	Magnesium chelatase ChlI-like, catalytic domain	Domain
A	IPR027417	P-loop containing nucleoside triphosphate hydrolase	Homologous Superfamily

Structure Motif Annotation: Mechanism and Catalytic Site Atlas M-CSA Database Homepage

Chains	Enzyme Name	Description	Catalytic Residues
A	magnesium chelatase M-CSA #536	Magnesium chelatase has a vital role in chlorophyll biosynthesis, using the energy from ATP hydrolysis to insert a Mg(II) ion into a porphyrin ring. It is part of a generic family of cellular ATPases known as AAA, displaying homology in particular to Cobalt Chelatase. Three subunits make up the overall protein in bacteria, BchI, BChlH and BChlD, also conserved in higher organisms. BChlI has ATPase activity and BChlH binds to the protoporphyrin group while BChlD has an regulatory allosteric role. Currently, there is limited experimental evidence to confirm a formal mechanism of magnesium chelatase with Arg 289 in BChlI being the only identifiable catalytic residue.	Defined by 1 residue: ARG:A-289 \| Explore in 3D: M-CSA Motif Definition At least 2 residues must be present to support Structure Motif searching.

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.